Clinical evaluation of rapid diagnosis of fungal keratitis by the combination of corneal scraping with laser scanning confocal microscopy / 中华实验眼科杂志

ABSTRACT

Background The rapid diagnosis can win more treating opportunities for patients with fungal keratitis.Even though the fungal culture is the gold standard for the diagnosis of fungal keratitis,it is difficult in early diagnosis due to the long duration of cultivation and false-negative rate.Objective This trial was to explore the clinical value in the rapid diagnosis of fungal keratitis by the combination of corneal scraping with laser scanning confocal microscopy.Methods Corneal scraping and laser scanning confocal microscopy were separately performed in 167 eyes of 167 patients with fungal keratitis.All the eyes were examined by the slit lamp,followed by laser scanning confocal microscope,and then the 10％ KOH corneal smear was examined under the optical microscope.Results The positive rate of diagnosis was 75％ (125/167) by corneal scraping,and that by laser scanning confocal microscopy was 91％ (152/167).The positive rate of examining outcome was significantly higher in laser scanning confocal microscopy than that of corneal scraping (x2 =14.88,P =0.00).The positive results were 114 cases and negative results were 4 cases by two methods,with the concordance rate 70.7％ (118/167).The hyphae or spore were seen in 32 cases by laser scanning confocal microscopy in 42 negative cases by corneal scraping,and in 15 negative cases by confocal laser scanning microscopy,11 positive outcomes were offered by corneal scraping.Conclusions The combined application of corneal scraping with confocal laser scanning microscopy can improve and speed up the diagnosis positive rate of fungal keratitis.